No offense, but I don’t think you’re going to have any luck with your sales for 3 reasons.
You have 0 trade rep
You only have 22 posts on this site and have been a member for less than a year.
You live in Poland (no offense to Polish people, it’s just hard enough trading with people outside the USA and Canada in general because of Customs and International Shipping Costs)
I suggest that if you want to get some sales, then you put a rule that you will ship first, but that the buyer has to have over 20 trade rep and has been a member for more than a year. That way, you aren’t getting scammed and neither is the other person. Good luck with your sales.